Are there any urinary side effects associated with fluoxetine (Prozac) and bupropion (Wellbutrin)?

From the Guidelines

Both fluoxetine (Prozac) and bupropion (Wellbutrin) can cause urinary side effects, although they are not the most commonly reported adverse effects. When considering the potential urinary side effects of these medications, it's essential to weigh the benefits against the risks, prioritizing morbidity, mortality, and quality of life.

• The provided evidence does not directly address urinary side effects associated with fluoxetine and bupropion 1.
• However, it does discuss various adverse effects associated with antidepressant medications, including SSRIs like fluoxetine, and highlights the importance of considering the overall adverse effect profile when selecting a medication 1.
• Given the lack of direct evidence on urinary side effects in the provided study, we must rely on general knowledge of these medications' mechanisms of action and potential side effects.
• Fluoxetine, as an SSRI, may influence bladder function due to its effects on serotonin, potentially leading to urinary retention, frequent urination, or difficulty urinating in some patients.
• Bupropion, affecting norepinephrine and dopamine, can also impact urinary tract function, with possible side effects including urinary frequency, urgency, and in rare cases, urinary retention.
• If patients experience persistent or bothersome urinary symptoms while taking these medications, it is crucial to consult a healthcare provider, who may adjust the dosage, recommend timing changes for taking the medication, suggest adequate hydration, or consider alternative medications if the side effects significantly impact quality of life.

From the FDA Drug Label

The most common adverse event (incidence at least 1% for fluoxetine and greater than placebo) associated with discontinuation in 3 pediatric placebo–controlled trials (N=418 randomized; 228 fluoxetine–treated; 190 placebo–treated) was mania/hypomania (1. 8% for fluoxetine–treated, 0% for placebo–treated). In these clinical trials, only a primary event associated with discontinuation was collected. Events observed in Prozac Weekly clinical trials — Treatment–emergent adverse events in clinical trials with Prozac Weekly were similar to the adverse events reported by patients in clinical trials with Prozac daily In a placebo–controlled clinical trial, more patients taking Prozac Weekly reported diarrhea than patients taking placebo (10% versus 3%, respectively) or taking Prozac 20 mg daily (10% versus 5%, respectively). Other adverse events in pediatric patients (children and adolescents) — Treatment–emergent adverse events were collected in 322 pediatric patients (180 fluoxetine–treated, 142 placebo–treated) The overall profile of adverse events was generally similar to that seen in adult studies, as shown in Tables 2 and 3 However, the following adverse events (excluding those which appear in the body or footnotes of Tables 2 and 3 and those for which the COSTART terms were uninformative or misleading) were reported at an incidence of at least 2% for fluoxetine and greater than placebo: thirst, hyperkinesia, agitation, personality disorder, epistaxis, urinary frequency, and menorrhagia Most common adverse reactions are (incidence ≥5%; ≥2× placebo rate): dry mouth, nausea, insomnia, dizziness, pharyngitis, abdominal pain, agitation, anxiety, tremor, palpitation, sweating, tinnitus, myalgia, anorexia, urinary frequency, rash. (6.1)

Urinary side effects associated with fluoxetine (Prozac) and bupropion (Wellbutrin) include:

• Urinary frequency 2, 3 These side effects have been reported in clinical trials for both medications.

From the Research

Urinary Side Effects of Fluoxetine and Bupropion

• Fluoxetine has been associated with urinary retention in some cases, as reported in a case study of a 15-year-old girl who experienced chronic urinary retention during fluoxetine monotherapy, which resolved after discontinuation of treatment 4.
• Another case study reported urinary retention in a patient taking a combination of fluoxetine and risperidone, suggesting that the combination of these medications may increase the risk of urinary retention 5.
• A systematic review of antipsychotic and antidepressant medications found that urinary retention was reported in 0.025% of patients on selective serotonin reuptake inhibitors, which includes fluoxetine 6.
• There is no direct evidence in the provided studies regarding the urinary side effects of bupropion.

Comparison with Other Medications

• Duloxetine, a dual reuptake inhibitor of serotonin and norepinephrine, has been found to have a low risk of urinary retention, with only 0.4% of patients reporting subjective urinary retention in clinical trials 7.
• A case study reported urinary retention in a patient taking a combination of duloxetine and olanzapine, highlighting the potential risk of urinary retention when combining medications 8.